Out-of-plane Excess Carrier Density Variations in Point Contact Lattice-based test Structures for QSSPC Contact Recombination Current Measurements

We report point contact spectroscopy measurements on YBa 2 Cu 3 O 7−δ thin films and textured bulk ceramics. The I(V) curves measured along the Copper-Oxygen (ab) plane direction are characteristic of the Andreev reflection phenomenon, with a sharp break at the gap edge. This allows a rather precise determination of the (in plane) gap, Δ = 20 mev . Subgap structure suggests the existence of a smaller gap for some orientations in the (ab) plane, of the order of 12 mev. The data also enabled us to set a lower bound to the inplane Fermi velocity in YBa 2 Cu 3 O 7−δ: v F ≥ 7 × 107 cm/sec . The value of v F has a crucial importance in the determination of the theoretical explanation for superconductivity in the High Temperature Superconductors. For out of plane measurements, only a weak zero bias anomaly is observed at energies up to 5 mev.

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Effects of Strain-Induced Defects on Excess Carrier Lifetime and Ambipolar Diffusion in nipi-Doped In0.2Ga0.8As/GaAs Mqws

MRS Proceedings ◽

10.1557/proc-379-275 ◽

1995 ◽

Vol 379 ◽

Author(s):

H.T. Lin ◽

D.H. Rich ◽

A. Larsson

Keyword(s):

Carrier Density ◽

Carrier Transport ◽

Carrier Lifetime ◽

Multiple Quantum Well ◽

Ambipolar Diffusion ◽

Structural Defects ◽

Multiple Quantum ◽

Coulombic Interaction ◽

Excess Carrier ◽

Induced Defects

ABSTRACTThe effects of strain-induced defects on excess carrier lifetime and transport in a nipi-doped In0.2Ga0.8As/GaAs multiple quantum well (MQW) structure were examined with a new method called electron beam-induced absorption modulation (EBIA) in which the kinetics of carrier transport and recombination are examined with a high-spatial, -spectral and -temporal resolution. The excess carrier lifetime and ambipolar diffusion were found to be reduced by factors of ∼1013 and ∼103 compared to theoretical values, respectively, and this is attributed to the presence of strain-induced defects. The MQW excitonic absorption coefficient sensitively depends on the carrier density in the QWs, as a result of screening of the electron-hole (e-h) Coulombic interaction. Likewise, ambipolar diffusion is found to depend on the excess carrier density in a nonlinear fashion, as a result of the e-h plasma-induced changes in the local depletion widths in the vicinity of structural defects.

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Effect of photocarriers on acoustic wave propagation for measuring excess carrier density and lifetimes in silicon

Applied Physics Letters ◽

10.1063/1.95084 ◽

1984 ◽

Vol 45 (11) ◽

pp. 1181-1183 ◽

Cited By ~ 4

Author(s):

R. G. Stearns ◽

B. T. Khuri‐Yakub ◽

G. S. Kino

Keyword(s):

Wave Propagation ◽

Acoustic Wave ◽

Carrier Density ◽

Acoustic Wave Propagation ◽

Excess Carrier

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The surface recombination velocity and bulk lifetime influences on photogenerated excess carrier density and temperature distributions in n-type silicon

Facta universitatis - series Electronics and Energetics ◽

10.2298/fuee1802313m ◽

2018 ◽

Vol 31 (2) ◽

pp. 313-328 ◽

Cited By ~ 7

Author(s):

Dragana Markushev ◽

Dragan Markushev ◽

Slobodanka Galovic ◽

Sanja Aleksic ◽

Dragan Pantic ◽

...

Keyword(s):

Carrier Density ◽

Surface Recombination ◽

Surface Recombination Velocity ◽

Excess Carrier ◽

Experimental Scheme ◽

Type Silicon ◽

Temperature Distributions ◽

Recombination Processes ◽

Sensitive Function ◽

Recombination Velocity

The temperature distributions in the n-type silicon circular plate, excited by a frequency-modulated light source from one side, are investigated theoretically in the frequency domain. The influence of the photogenerated excess carrier density on the temperature distributions is considered with respect to the sample thickness, surface quality and carrier lifetime. The presence of the thermalization and non-radiative recombination processes are taken into account. The existence of the fast and slow heat sources in the sample is recognized. It is shown that the temperature distribution on sample surfaces is a sensitive function of an excess carrier density under a bulk and surface recombination. The most favorable values of surface velocities ratio and bulk lifetime are established, assigned for a simpler and more effective analysis of the carrier influence in semiconductors. The photothermal and photoacoustic transmission detection configuration is proposed as a most suitable experimental scheme for the investigation of the excess carrier influence on the silicon surface temperatures.

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Excess carrier density and forward voltage drop in trench insulated gate bipolar transistor (TIGBT)

2002 23rd International Conference on Microelectronics. Proceedings (Cat. No.02TH8595) ◽

10.1109/miel.2002.1003170 ◽

2003 ◽

Author(s):

Hyoung-Woo Kim ◽

Min-Su Kim ◽

Yearn-Ik Choi ◽

Sang-Koo Chung

Keyword(s):

Carrier Density ◽

Voltage Drop ◽

Bipolar Transistor ◽

Forward Voltage ◽

Excess Carrier ◽

Insulated Gate Bipolar Transistor ◽

Forward Voltage Drop

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Temperature dependence of excess carrier density and thermopower in tin-doped bismuth. Pseudo-parabolic model

Journal of Physics C Solid State Physics ◽

10.1088/0022-3719/16/23/022 ◽

1983 ◽

Vol 16 (23) ◽

pp. 4623-4636 ◽

Cited By ~ 21

Author(s):

J Heremans ◽

O P Hansen

Keyword(s):

Temperature Dependence ◽

Carrier Density ◽

Parabolic Model ◽

Excess Carrier

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Carrier Diffusivity in Highly Excited Bulk SiC, GaN, and Diamond Crystals by Optical Probes

Materials Science Forum ◽

10.4028/www.scientific.net/msf.717-720.309 ◽

2012 ◽

Vol 717-720 ◽

pp. 309-312 ◽

Cited By ~ 4

Author(s):

Kęstutis Jarašiūnas ◽

Patrik Ščajev ◽

Tadas Malinauskas ◽

Masashi Kato ◽

Evgenii Ivakin ◽

...

Keyword(s):

Diffusion Coefficient ◽

Carrier Density ◽

Room Temperature ◽

Wide Bandgap ◽

Optical Monitoring ◽

Excess Carrier ◽

Carrier Scattering ◽

Diamond Crystals ◽

Bandgap Semiconductors ◽

The Impact

Optical monitoring of diffusivity in wide bandgap semiconductors was performed by using a picosecond light-induced transient grating technique. The bandgap renormalization and carrier-carrier scattering manifested itself at room temperature as two-fold decrease of the ambipolar diffusion coefficient Da in cubic SiC and 5-fold decrease of Da in diamond at excess carrier density N > 1017cm-3, while for GaN the impact was observed only at T 19cm-3, the plasma degeneracy led to enhanced Davalues in SiC and GaN and compensated the diffusivity decrease in diamond.

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INVESTIGATIONS ON THE DIFFUSION OF MINORITY CARRIERS FROM A POINT ON SILICON

Canadian Journal of Physics ◽

10.1139/p61-083 ◽

1961 ◽

Vol 39 (5) ◽

pp. 754-767 ◽

Cited By ~ 1

Author(s):

C. H. Champness

Keyword(s):

Carrier Density ◽

Type Material ◽

Free Diffusion ◽

Effective Lifetime ◽

Surface Theory ◽

Flat Surfaces ◽

Excess Carrier ◽

Decay Times ◽

P Type ◽

Minority Carriers

The field-free diffusion of minority carriers injected at a point in silicon has been studied and the time from injection to the maximum of the collector signal due to the arriving carriers measured for various emitter–collector distances. Firstly, it was found that for 2-ohm-cm, 6-microsecond, n-type material the time to maximum was proportional approximately to the emitter–collector spacing raised to the power 1.2 for flat surfaces and to the power 1.6 for 3- and 6-degree wedge samples. The power 1.6 was also found for a 17-degree wedge of 120-ohm-cm, 100-microsecond, p-type silicon. Secondly, decay times following the maxima appeared to increase with emitter–collector spacing. No adequate two-surface theory is available but comparison with a one-surface theory revealed serious disagreements. It would appear that the results may be explained qualitatively by assuming that the effective lifetime is dependent on the excess carrier density and decreases as the emitter point is approached.

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